1. Field of the Invention
The embodiments discussed herein relate a semiconductor module manufacturing method and a semiconductor module.
2. Background of the Related Art
A semiconductor module includes semiconductor elements mounted on a die pad portion and a lead portion electrically connected to the semiconductor elements via wirings, and these components are encapsulated with encapsulation resin. When such a semiconductor module is manufactured, the die pad portion and the semiconductor elements are inserted into a cavity in a transfer molding die formed by upper and lower dies, and resin is injected into the cavity where the lead portion is sandwiched between the upper and lower dies. In this manufacturing process, if there is space between the lead portion and the pair of the upper and lower dies, the resin flows into the space, and a burr is formed on the lead portion. To prevent the formation of such a burr, a method has been proposed. According to this method, a protruded portion is arranged at an end portion of a lead portion, and inflow of resin is prevented thereby (see, for example, Japanese Laid-open Patent Publication No. 06-216293).
There is a semiconductor module that includes a plurality of power semiconductor elements and that is used as a power conversion device or a switching device. For example, there is a semiconductor module that is allowed to function as a switching device by connecting semiconductor chips including an insulated gate bipolar transistor (IGBT), a metal-oxide semiconductor field-effect transistor (MOSFET), etc. in parallel to each other (see, for example, Japanese Laid-open Patent Publication No. 2014-90016).
Such a semiconductor module is also manufactured by inserting an insulating substrate, semiconductor elements, a printed substrate, and an external terminal into a cavity in a transfer molding die and injecting resin into the cavity.
However, as is the case with Japanese Laid-open Patent Publication No. 06-216293, the semiconductor module discussed in Japanese Laid-open Patent Publication No. 2014-90016 also has the same problem. Namely, the resin flows into the space between the transfer molding die and a pin-shaped external terminal, and a burr is formed on the external terminal. If a burr is formed, the chance that the electrical continuity of the pin-shaped external terminal is deteriorated is increased. If the electrical continuity is deteriorated, since an adequate function or adequate performance of the semiconductor module is not obtained, there is a possibility that characteristics of the semiconductor module are deteriorated.